Research And Application Of DMA In Image Acquisition And Processing System

Digital signal processor(DSP)were widely used in processing,industrial,artificial intelligence,and scientific computing because of their outstanding advantages such as low cost,low power consumption,and high performance.However,people's requirements for data transmission speed of the equipment are getting higher and higher.If the CPU was used to perform frequent interrupt operations,the data transmission speed of the DSP could not meet the application requirements.32-bit high-precision DSP with integrated DMA modules have been studied in this paper.Data was transmitted through the DMA mode in the DSP,it not only speeded up the DSP processor but also improved the overall system's processing power.The Direct Memory Access(DMA)module was an important part of the X-type DSP.It used hardware to transfer high-speed data between internal and external memories and I/O devices.When the DMA was responded to the data transmission request,Direct Memory Controller(DMAC)could control its internal data bus,address bus,and control bus without CPU,eliminated the need for addressing instructions that the CPU must handle when transmitting.Firstly,the DSP system environment was introduced.Secondly,the architecture of the DMA module in X-type DSP and the behavior design of each internal module were introduced in detail.Finally,the DMA module function was verified through system-level simulation.According to the problem of the original image acquisition and processing ID card recognition system could not quickly move a large amount of AD sampling data to an external SDRAM and greatly wasted ADC internal resources in the DSP.The DSP without integrated DMA module in the original system was replaced by X-DSP.A data path was provided by the internal DMA module between the ADC module in the DSP and the external memory interface XINTF to improve the efficiency of the algorithm.The structure of each module within the original system was introduced.The necessity of using the DMA module to optimize the design of the original system was analyzed.The design of a new system consisting of CMOS image sensors,photoelectric sensors,X-DSP,FPGA,SDRAM,and USB3.0 interfaces were specifically introduced.The four parts of the new system's image acquisition module,image processing module,DSP program boot loading module,system and host computer communication module were designed.Finally,the correctness of the new system's design was verified through product testing.